1. Field of the Invention
This invention relates generally to inflatable boats, and more particularly to gas inlet valve apparatus for inflatable boats.
2. Description of the Prior Art
Inflatable boats, and particularly life rafts, are most commonly stored in the deflated, folded configuration. Compressed inflation gas, often carbon dioxide, is provided in bottles associated with the life rafts, and is released into inflation chambers of the life raft by manipulation of a pull-cord or other device. The compressed gas flows through a suitable conduit into one or more of the inflation chambers. Check valves at the point of entry into the inflation chambers keep the gas sealed within the inflation chambers. These check valves typically have a valve body with at least one inlet opening, one or more outlet openings, and a check valve member disposed between the inlet opening and the outlet openings. The compressed gas is typically under great pressure so as to rapidly inflate the inflation chamber. These pressures can be in excess of 9,000 psi. The compressed gas expands upon entering the inflation chamber, and undergoes a very great pressure change which cools the gas to very cold temperatures. Gas jets emanating from the outlet openings impact directly on adjacent wall portions of the inflation chamber, and the very cold temperatures can cause freezing and cracking of these areas. Also, rapid inflation will cause icing of the carbon dioxide, and ice formation in the inflation chamber and on the inlet check valve. These are especially significant problems where the life raft is to be used in very cold climates, and air temperatures can be -60 degrees F., or less.
Apparatus have been provided to alleviate the problem caused when cold inflation gases impact inflation chamber surfaces. One such apparatus is an elongated, porous sleeve having a longitudinal passage and a side opening. The sleeve is positioned over the gas inlet valve with the outlet openings within the side opening of the sleeve. Gas emanating from the outlet openings passes axially through the longitudinal passage toward either end of the sleeve, and is dispersed through the sleeve material into the inflation chamber. The sleeve must be of a relatively large dimension, usually more than two feet in length, is expensive to manufacture, and is difficult to store within a compact, folded, and deflated life raft construction.